Clients lose access to network shares on server

Question

I have a problem with all the network clients (Win10) losing there access to the network shares on the server (SBS2011/2008 R2). This happens to all the clients at the same time.
When this happens, I can't ping the server, but can remotely access it via Teamviewer. All clients can still send and receive email through the server.
Unfortunately I don't have a lot of time to troubleshoot and figure out what's going on when this happens, because all the staff lose their access and need it restored asap.

Figured I would try restarting LanmanServer service, but when the the LanmanServer service attempts to stop, it fails and can't be force stopped. Seemingly the only way to fix the problem is to reboot the server.

The Application Log (in this last occurence) showed a failure accessing a network share on the server for an Exchange pst export that I was running at the time. So I know exactly what time the problem occured.
But there's nothing else in the Application log immediately before it.
And there's nothing in the System event logs prior to the client's being disconnected either. There's nothing in any of the logs to show any cause.

Initially I thought it was a backup task running over time and causing problems with network connectivity, but that doesn't seem to be the case (having disabled the particular backup), though it has occurred less often since disabling this backup.

Help appreciated.

Answer 1

The domain controller SERVER-01 is multi-homed because of the RRAS role. Multi-homing a domain controller always causes no end to grief for active directory DNS. I'd remove RRAS role from domain controller and install it on a member server. I'd didn't look at the other files since this one is a show stopper. After correcting issues, if problems persist then put up a new set of files to look at.

--please don't forget to Accept as answer if the reply is helpful--

Answer 2

I'd check the domain controller and problem member both have the static ip address of DC listed for DNS and no others such as router or public DNS

--please don't forget to Accept as answer if the reply is helpful--

Answer 3

Please run;

Dcdiag /v /c /d /e /s:%computername% >c:\dcdiag.log
repadmin /showrepl >C:\repl.txt
ipconfig /all > C:\dc1.txt
ipconfig /all > C:\problemworkstation.txt

also the source and event ID's for any event log errors since last boot may be helpful

then put unzipped text files up on OneDrive and share a link.